System Administration Guide: Advanced Administration

Port Monitors

The main mechanism for gaining access to a service is through a port monitor. A port monitor is a program that continuously monitors for requests to log in or access printers or files.

When a port monitor detects a request, it sets whatever parameters are required to establish communication between the operating system and the device requesting service. Then, the port monitor transfers control to other processes that provide the services needed.

The following table describes the two types of port monitors included in the Oracle Solaris release.

Table 1–1 Port Monitor Types

Man Page 

Port Monitor 




Controls access to network services, such as handling remote print requests prior to the Solaris 2.6 release. The default Oracle Solaris OS no longer uses this port monitor type.



Provides access to the login services needed by modems and alphanumeric terminals. The Serial Ports tool automatically sets up a ttymon port monitor to process login requests from these devices.

You might be familiar with an older port monitor called getty. The new ttymon port monitor is more powerful. A single ttymon port monitor can replace multiple occurrences of getty. Otherwise, these two programs serve the same function. For more information, see the getty(1M) man page.